Recent attacks on the Polish rail network and growing pressure on power grids show how grey zone tactics have moved from theory into daily reality. They also demonstrate the continuing importance of physical protection for critical sites.

Understanding Grey Zone Warfare

Grey zone operations include sabotage, cyber intrusion, misinformation and low level physical interference. The objective is simple. Increase the cost of defence, delay logistics, damage confidence and test political cohesion. These attacks offer plausible deniability and reduce the risk of escalation.

Operators of national infrastructure are now confronting a threat landscape that is both ambiguous and persistent.

Case Study: Attacks on Poland’s Rail System

In late 2025 the Polish government confirmed an explosion on a key railway line frequently used for transport to Ukraine. Previous incidents included deliberate track interference, targeted infrastructure damage and radio attacks that sent unauthorised emergency stop signals to multiple trains.

These events share common characteristics. They target high value logistics routes. They exploit older systems with weak communication security. They focus on areas where physical protection is limited. Attribution is still ongoing but analysts continue to connect these disruptions to hostile state activity.

Pressure on Power Grids and Energy Networks

Power grids across NATO’s eastern flank have also faced increasing levels of interference and attempted intrusion. From drone flyovers to attempts to access substations, operators have been compelled to strengthen their sites with new protective compounds, anti drone measures and rapid detection systems.

Energy networks are attractive targets because a single point of failure can create national level disruption.

Why Physical Security Matters

Grey zone attacks often rely on speed, access and concealment. Upgrading physical security disrupts all three. Strong perimeter protection is a force multiplier for both detection and response.

Below are the main ways that fencing and secured compounds help protect infrastructure.

1. Delaying and Denying Access

High security fencing systems, including LPS 1175 certified products, create meaningful delay. Attackers must commit time, tools and noise which increases the chances of detection. For rail hubs, substations and fuel depots this delay can be the difference between a protected asset and a successful act of sabotage.

2. Creating Clear Boundaries

Many legacy sites have weak or unclear boundaries. Upgraded fencing creates a defined perimeter that supports CCTV, PIDs, patrol routes and access control. Clear borders remove ambiguity and make intrusion easier to detect.

3. Resistance to Basic Tools

Grey zone saboteurs often use basic equipment such as bolt cutters, pry bars or lightweight explosives. Mesh systems with certified cut resistance, anti-climb geometry and tamper-resistant fixings dramatically reduce the success of these tactics.

4. Integration With Security Technology

Modern perimeter protection is designed to integrate with electronic systems. This includes sensors, fibre detection, microwave barriers and automated alarms. A fence line becomes an active detection asset rather than a passive barrier.

5. Supporting Redundancy and Resilience

Physical protection remains essential even when cyber systems are compromised. Strong perimeters prevent unauthorised access to control cabinets, switching systems and trackside equipment.

A Growing European Pattern

Europe has seen a rise in attacks on rail signalling, energy infrastructure, maritime cables and logistical corridors. Many of these incidents remain unattributed. What is clear is that physical intrusion opportunities play a major role in enabling them.

The Path Forward

Grey zone activity is not a temporary trend. It will remain a feature of European security for years. While governments continue to improve cyber defence, physical protection must not be neglected. Perimeter security is often the first and most reliable line of defence.

Upgrading fencing, access control and detection capability is a cost effective and practical way to reduce risk. When a site is protected by certified systems, the attacker’s timeline is disrupted, detection thresholds are lowered and the likelihood of success drops sharply.

Conclusion

The attacks in Poland and the broader pressure across Europe illustrate the urgent need to strengthen both physical and technological defences. Grey zone warfare relies on exploiting gaps. Strong fencing, secure boundaries and integrated detection systems close many of those gaps.

For critical national infrastructure, effective perimeter protection is no longer optional. It is essential for resilience, continuity and national stability.

The post Silent Fronts: Grey Zone Warfare and the Protection of Europe’s Critical Infrastructure appeared first on Zaun Limited.

Why weld strength matters more than just wire gauge

In the world of 358 mesh fencing, not all panels are created equal. Many companies market panels by quoting wire thickness such as 3.9 mm, 4.0 mm, etc. But that metric alone doesn’t tell the full story.

We recently carried out a series of destruction tests on three 358 panels to compare real-world performance. The results show why relying on wire thickness alone can leave your perimeter exposed. We chose 358 as it is often seen as a High Security Fencing system and therefore a safe panel for many projects such as schools, transport and logistics, and commercial projects.

The Test Setup & Results

Panel	Origin	Wire Diameter (mm)	Failure Load	% of Wire Tensile	Result
Panel 1	UK	3.96 – 3.99	4.9 kN	~75%	PASS
Panel 2	Turkey	3.76 – 3.77	2.4 kN	36.64%	FAIL
Panel 3	China	3.86 – 3.90	0.8 kN	12.21%	FAIL

Panels 2 and 3 are currently being sold into the UK market, despite failing at less than half, and in one case less than one-sixth, of the strength of the UK-manufactured panel. How do we know? Because the manufacturers approached us directly and sent these very samples as their best examples. They even told us which UK fencing companies they already supply.

“These weren’t random imports. The manufacturers sent us these samples as their best panels to prove quality. They still failed.”

Why Weld Strength Is the Real Gatekeeper

“A mesh fence is only as strong as its weakest weld.”

1. The weakness is at the joints

In a mesh panel, the points where wires cross are welded. If those welds are poorly made, for example under-penetrated, porous, or inconsistent, they will fail well before the wire itself breaks. This is exactly what we saw in Panels 2 and 3.

2. Wire thickness ≠ panel strength

Thicker wire alone doesn’t always guarantee security. In our test, the Chinese panel used almost the same wire size as the UK panel, but it still failed at just 0.8 kN. The reason, its welds could not sustain the load.

3. Real-world loads demand reliable welds

From crowd loading to climbing attempts, fences experience repeated stresses and sudden impacts. If welds crack or shear under these loads, the perimeter is compromised. International standards specify testing because weld quality is mission-critical.

4. Quality control makes the difference

Strong panels require not just the right design, but also rigorous inspection and destructive sampling. That’s what ensures every batch performs consistently, not just on paper.

What to Ask Your Supplier

• Weld shear test data – not just wire diameter.
• Batch quality control – how often are destructive tests run?
• Standards compliance – do they meet BS 1722 requirements?

Watch the Test for Yourself

It is not the size of the wire that keeps a site secure, it is the strength of the weld. In our tests, the UK panel withstood more than double the destructive load of the Turkish panel, and over six times that of the Chinese panel.

The Turkish panel had the thinnest wire (average 3.765 mm), around 5.3% thinner than the UK panel (average 3.975 mm). It performed better than the Chinese panel (average 3.88 mm), but still failed at less than 40% of the overall tensile strength. The Chinese panel failed at less than 13% of the overall tensile strength. The UK panel passed at 4.9 kN, equal to 75% of the tensile strength.

You can see the results for yourself in the video below:

Final Word

Don’t be misled by numbers on a datasheet. A panel can look the same and feel the same but when tested, weak welds fail well before the wire does.

If you’re responsible for protecting a perimeter, insist on weld test data, not just wire thickness. It is the welds that stand between a secure site and a serious breach.

We invite you to visit our mesh manufacturing facility and see a destruction test in person. Contact us today to arrange your visit.

The post Who’s Really Protecting Your Perimeter? appeared first on Zaun Limited.

The event and factory tour were arranged by The Black Country Chamber of Commerce to allow Heathrow to meet one of their supply chain members in the form of Zaun. Heathrow spends almost £100m every year in the West Midlands via their supply chain. Nigel was able to see how Zaun has been innovating and decarbonising physical perimeter security fencing and gate systems that are deployed at Heathrow.

From all electric Forklift trucks to a 330mw Solar Array and British Manufacturing, Zaun were able to share part of their journey to ‘greener security’. Nigel Milton said, “Heathrow relies on SMEs up and down the country, and it is fantastic to come out and meet with the companies that keep the UK’s hub airport flowing.”

The tour was hosted by Alastair Henman (Founder and Managing Director), Jack McGinty (Operations Director), and Steve Bailes (Business Development Manager) for Zaun. (Pictured left to right – Gail Arnold (Black Country Chamber of Commerce), Steve Bailes (Zaun), Alastair Henman (Zaun), Jack McGinty (front- Zaun), Dave Goss (back – Fernden Construction), Sarah Ralphs (Heathrow), Paul Bovington (Fernden Construction), Nigel Milton (Heathrow)

The post Airport Security – Driving Innovation in decarbonising physical perimeter security appeared first on Zaun Limited.

We were on the tarmac at Berlin and Munich #airports addressing the causes of climate change.
With fossil fuel subsidies for aviation, it would be easy to make local transport affordable.

The police were informed in advance. There is no danger from us – but from #DeadlyPolitics! pic.twitter.com/KdZ9skrRlx

— Letzte Generation (@AufstandLastGen) December 8, 2022

On 26^th November a group of six activists cut through the physical perimeter of BER Berlin Brandenburg Airport to gain access to the taxiways. In the 16 minutes that they had uninterrupted access before the Federal Police arrived, they managed to glue themselves to the tarmac. Their actions resulted in fifteen incoming flights being rerouted and five others grounded.

Two weeks later on 8^th December, the same group carried out an identical intrusion into MUC Munich International Airport and again at BER. Gaining access again by ‘cutting through’ the active perimeter fence line allowed them to superglue their hands to not only taxiways but one of the active runways. Last Generation claims to have informed the Federal Police about their plans and documented the protest across multiple social media channels.

 

 

 

 

 

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A post shared by Sibylle Fendt (@sibyllefendt)

In both incursions, the airport’s physical perimeter and detection systems failed to protect the airport from unauthorised access. Standard chain link fencing had been installed with barbed wire hostile security topping to prevent scaling. The threat from cut-through appears to have not been considered and so the adoption of tested and certified fencing systems such as LPS 1175, Secured by Design, or fencing ‘Approved for Government Use – CPNI’ seems to have been discounted in the threat analysis.

Zaun has worked with a number of major airports to secure their perimeters against attacks over the years. With this ‘proven’ disruption seeming to work in Germany, is it now time for other airports to readdress the threats to their estate from climate protesters?  

The post Physical Security Failures close both Berlin and Munich Airport appeared first on Zaun Limited.